Golf ball manufacturers produce golf balls such that dimples are formed in the outer surface. The dimples on a golf ball are important in manipulating the aerodynamic forces generated by a ball in flight as a result of the ball's velocity and spin. Recently, golf ball manufacturers have found that by varying the hardness of the dimple, different spin characteristics may be exhibited.
However, if a golf ball designer wants to make a golf ball with dimples containing multiple hardnesses, they cannot do so with a single layer. Rather, the most common way of creating a golf ball dimple with multiple hardness regions is to construct a ball in which the underlying layer protrudes into specific regions of the cover layer, thereby partially filling in the desired portion of the dimple. Later, an additional layer, in most cases a castable liquid, is applied thus forming a complete dimple. However, this process requires the use of at least two different layers.
Accordingly, there remains a need for golf balls having dimples exhibiting multiple hardness regions but formed from a single layer to enhance the aerodynamic performance of the golf ball.